LUMIERA.clone/src/proc/control/argument-erasure.hpp

89 lines
2.4 KiB
C++

/*
ARGUMENT-ERASURE.hpp - helper for passing on a dynamic typed argument tuple
Copyright (C) Lumiera.org
2009, Hermann Vosseler <Ichthyostega@web.de>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef CONTROL_ARGUMENT_ERASURE_H
#define CONTROL_ARGUMENT_ERASURE_H
#include "lib/error.hpp"
namespace proc {
namespace control {
LUMIERA_ERROR_DECLARE (INVALID_ARGUMENTS); ///< Arguments provided for binding doesn't match stored command function parameters
/**
* Adapter interface for invoking an argument binding for a command
* \em without the need to disclose the concrete types and number of arguments.
* At the receiver side, the concrete type can be restored by a dynamic cast.
* This requires the receiver somehow to know the desired argument types;
* usually this receiver will be an implementation object, whose exact
* type has been erased after definition, while the implementation
* internally of course knows the type and thus can perform an
* dynamic cast on the passed on argument tuple
*/
struct Arguments;
template<typename TUP>
struct TypedArguments;
struct Arguments
{
virtual ~Arguments() {}
template<typename TUP>
TUP const&
get ()
{
TypedArguments<TUP>* dest = dynamic_cast<TypedArguments<TUP>*> (this);
if (!dest)
throw lumiera::error::Invalid("Wrong type or number of arguments"
, LUMIERA_ERROR_INVALID_ARGUMENTS);
return dest->args_;
}
};
template<typename TUP>
struct TypedArguments
: Arguments
{
TUP const& args_;
TypedArguments (TUP const& a)
: args_(a)
{ }
};
}} // namespace proc::control
#endif